Authorities are scrambling to learn more about the attack, including a motive, and they’re looking at the 38-year-old suspect’s personal YouTube account for clues. Aghdam’s channel allegedly contained extremist vegan, pro-animal rights content. According to her social media pages, the woman felt YouTube was regulating her channel and trampling her right to free speech.

Many couldn’t help but see the irony of YouTube being targeted by an alleged vegan extremist with a gun — including Donald Trump Jr., who used the shooting as an opportunity to mock the anti-gun agenda. He went off on a NRA-friendly rant on Twitter.

You think there’s any chance whatsoever that a mass shooters hateful Instagram and YouTube channels would be pulled immediately if they were NRA members as opposed to liberal Vegan PETA activists? Asking for a few million friends in the @NRA

Some users agreed with Trump Jr.’s assessment of the shooting. However, many criticized the businessman for making light of the attack, which injured several people. They blasted Trump Jr. on Twitter.

"Asking for a [few million] friend[s]" is a sort of immature way to address a serious issue like mass shooting. I wouldn't expect anything else from you. Stay out of policy, it's not your thing, kind of like property management.

Trump Jr. did not respond to the backlash; he continued tweeting and retweeting comments such as, “PETA has more mass shooters than the NRA,” and “PETA is a terrorist organization.”

PETA previously commented on Donald Trump Jr. saying, “The Trump sons would shoot their own mother if she was on four legs. There’s nothing funny about the super-privileged depriving the less privileged of all they value, including their lives, and PETA reminds their father that he used to condemn them for fishing and hunting, saying that he didn’t understand how they could. Neither do we.”